In the current study, patient-reported outcomes were assessed at day 1 of cycles 1 to 3, every 9 weeks thereafter, at the treatment discontinuation visit, and at the 30-day safety assessment visit using the European Organisation for the Research and Treatment of Cancer (EORTC) Quality-of-Life Questionnaire Core 30 items (QLQ-C30) and the EORTC Quality-of-Life Questionnaire Lung Cancer 13 items (QLQ-LC13). The primary exploratory patient-reported outcome endpoints were change at week 15 in the QLQ-C30 global health status/quality-of-life score and time to deterioration of the composite of cough, chest pain, and dyspnea in the QLQ-LC13. Time to deterioration was defined as the time to first onset of a ≥ 10-point decrease from baseline in cough, chest pain, or dyspnea, confirmed by a second adjacent ≥ 10-point decrease from baseline in any of the three symptoms.

Improved Patient-Reported Outcomes

Patient-reported outcomes compliance was > 90% at baseline and approximately 80% at week 15 for both groups. The least-squares mean baseline to week 15 change in QLQ-C30 global health status/quality-of-life score was 6.9 in the pembrolizumab group vs −0.9 in the chemotherapy group (difference = 7.8, P = .0020). As noted by the authors, although improvements of ≥ 10 points on this measure have been viewed as clinically meaningful, differences as low as 4 points have been reported to represent minimally important differences in NSCLC trials. Deterioration in the QLQ-LC13 composite endpoint was observed in 31% vs 39% of patients. The median time to deterioration was not reached in the pembrolizumab group vs 5.0 months in the chemotherapy group (hazard ratio = 0.66, P = .029).

The investigators concluded: “Pembrolizumab improves or maintains health-related [quality of life] compared with that for chemotherapy, and might represent a new first-line standard of care for PD-L1-expressing, advanced NSCLC.”